Alzheimer's Disease May Be Misdiagnosed

Feb. 23, 2011 -- Alzheimer’s disease and other dementias that occur late in life are easily misdiagnosed, new research indicates.

Researchers autopsied the brains of 426 Japanese-American men who lived in Hawaii and died at an average age of 87.

Of those, 211 were diagnosed with dementia when they were alive, and the dementia was most commonly attributed to Alzheimer’s disease.

But the autopsies found that only about half of those diagnosed with Alzheimer’s had brain findings consistent with the disease, such as amyloid plaques and neurofibrillary tangles. Rather, most of those diagnosed with Alzheimer’s that was not confirmed had a combination of other brain abnormalities sufficient to explain dementia, including Lewy bodies, hippocampal sclerosis, or generalized brain atrophy.

Complex Diagnosis

“Diagnosing specific dementias in people who are very old is complex, but with the large increase in dementia cases expected within the next 10 years in the United Sates, it will be increasingly important to correctly recognize, diagnose, prevent and treat age-related cognitive decline,” study researcher Lon White, MD, MPH, of the Kuakini Medical System in Honolulu, says in a news release.

“Larger studies are needed to confirm these findings and provide insight as to how we may more accurately diagnose and prevent Alzheimer’s disease and other principal dementing disease processes in the elderly,” White says.

Dementia can have several causes, including Alzheimer’s disease. Initial symptoms in people with Alzheimer’s disease usually start after age 60. Alzheimer’s disease is the most common cause for dementia in the U.S.

The study will be presented in Honolulu during the 2011 annual meeting of the American Academy of Neurology.

This study will be presented at a medical conference. The findings should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.